1. Field of The Invention
The present invention relates to the field of transformers and battery chargers, and more particularly, the field of transformer battery chargers.
2. Description of The Prior Art
Transformers are old in the art. Battery chargers have also been developed with the utilization of rechargeable batteries. There are certain types of battery chargers which have utilized transformers as part of their assemblies. The following thirteen (13) prior art patents have been uncovered, which are relevant to the pertinent fields of art.
1. U.S. Pat. No. 2,375,309 issued to McCoy on May 8, 1945 for "High Frequency Transformer" (hereafter the "McCoy Patent").
2. U.S. Pat. No. 2,967,267 issued to Steinman et al. on Jan. 3, 1961 for "Reactive Intercoupling of Modular Units" (hereafter the "Steinman Patent").
3. U.S. Pat. No. 3,108,763 issued to Ahlene on Oct. 29, 1963 for "Coil Form" (hereafter the "Ahlene Patent").
4. U.S. Pat. No. 3,346,828 issued to Buschman on Oct. 10, 1967 for "Transformer Assembly For Varying Electrical Parameters And Method Of Constructing The Same" (hereinafter the "Buschman Patent").
5. U.S. Pat. No. 3,418,552 issued to Holmes on Dec. 24, 1968 for "Separable Transformer Battery Charger" (hereafter the "Holmes Patent").
6. U.S. Pat. No. 3,549,990 issued to Hochheiser on Dec. 22, 1970 for "Non-Sparking A-C Connectors" (hereafter the "Hochheiser Patent").
7. U.S. Pat. No. 3,544,937 issued to Boysen on Dec. 1, 1970 for "Coil Supporting Plates" (hereafter the "Boysen Patent").
8. U.S. Pat. No. 3,675,108 issued to Nicholl on Jul. 4, 1972 for "Induction Charging Device" (hereafter the "Nicholl Patent").
9. U.S. Pat. No. 3,840,795 issued to Roszyk et al. on Oct. 8, 1974 for "Hand Held Battery Operated Device And Charging Means Therefor" (hereafter the "Roszyk Patent").
10. U.S. Pat. No. 4,250,479 issued to Bausch et al. on Feb. 10, 1981 for "Transformer Bobbin Assembly" (hereafter the "Bausch Patent").
11. U.S. Pat. No. 4,257,027 issued to Yasuhisa on Mar. 17, 1981 for "Transformer Bobbin Assembly" (hereafter the "Yasuhisa Patent").
12. U.S. Pat. No. 4,661,792 issued to Watkins on Apr. 28, 1987 for "Apparatus For Mounting Printed Circuit Boards" (hereafter the "Watkins Patent").
13. U.S. Pat. No. 4,916,424 issued to Kijima on Apr. 10, 1990 for "Electric Part In The Form Of Windings" (hereafter the "Kijima Patent").
Most of the above referenced prior art patents are related to the design and construction of transformers themselves, or simply the design and construction of transformer bobbins alone. The only prior art patents related to the design and construction of transformer battery charger assemblies are the Holmes Patent and the Roszyk Patent. In addition, there is only one prior art patent, the Watkins Patent, which is related to the technique of mounting a printed circuit board (hereafter referred to as "PCB") together with a transformer assembly.
The Watkins Patent discloses an apparatus for mounting a primary PCB, a secondary PCB and a transformer. The mounting apparatus includes a bobbin having standoffs for supporting the secondary PCB in a parallel relationship with the primary PCB, and retaining the transformer therebetween. The standoffs have many connector pins for alignment. The Watkins Patent, however, is generally related to large PCBs used in major electronic equipment such as computers. It is not related to an apparatus for recharging rechargeable batteries.
The Holmes Patent discloses a separable transformer battery charger, which is utilized in an automatic toothbrush pack. The primary winding is retained with a base, and the secondary winding is retained with the toothbrush handle. The primary winding and secondary windings are positioned in stacked relationship and flux-linked by a common magnetic stud. Half of the stud extends through the primary winding and the other half extends through the secondary winding. The Holmes Patent is not designed for recharging independent rechargeable batteries and does not have any electronic circuitry for monitoring and controlling the charging process.
The Roszyk Patent discloses a transformer battery charger, which is also utilized in an automatic toothbrush pack. The primary winding is retained with a base, and the secondary winding is retained with the toothbrush handle. The primary winding and secondary winding are positioned in either stacked or side-by-side relationships. Again, the Roszyk Patent is not designed for recharging independent rechargeable batteries and does not have any electronic circuitry for monitoring and controlling the charging process.
The following prior art patents are generally related to the design and construction of transformers.
The McCoy Patent discloses a transformer assembly which has separable bobbins. The cylindrical secondary bobbin is placed within the hollow cylindrical primary bobbin. A flat supporting plate is utilized for retaining the primary and secondary bobbins. The McCoy Patent is related to the transformers used for transferring radio frequencies.
The Buschman Patent discloses a transformer assembly with standard interchangeable cores and windings. The two interchangeable windings are retained by the core in a stacked relationship.
The Hochheiser Patent discloses an alternate current (AC) connector which includes a transformer assembly. The transformer assembly includes a plurality of pairs of U-shaped primary and secondary windings. Each pair of primary and secondary windings are oppositely disposed with a narrow gap in between.
The Boysen Patent discloses a pair of bobbin supporting plates. The pair of supporting plates are disposed in parallel relationship and support two transformer bobbins in a side-by-side relationship.
The Kijima Patent discloses a five-piece transformer assembly. The five-piece transformer assembly includes an inner bobbin, a top half piece and a bottom half piece which form an outer bobbin, and two E-shaped cores. The inner bobbin is aligned with the outer bottom piece by several pins.
The following prior art patents are simply related to the design and construction of transformer bobbins. The Ahlene Patent discloses a bobbin assembly which is formed by six individual flat pieces. The six pieces are interlocked with one another to form a generally rectangular shaped bobbin.
The Yasuhisa Patent discloses a four-piece bobbin assembly. The four-piece bobbin assembly includes an outer frame bobbin, an inner frame bobbin and a pair or protective covers.
The Bausch Patent discloses a bobbin assembly which includes a pair of primary-secondary shields for interlinking one primary bobbin and two secondary bobbins. The primary bobbin is sandwiched between the two secondary bobbins.
The rest of the prior art patents are generally related to the assemblies of electronic components. The Steinman Patent discloses an intercoupling modular assembly, which includes a multiplicity of modular units intercoupled and retained in a rectangular shaped cabinet. Each of the modulars may be independently removed and replaced. The Steinman Patent is related to electronic equipment, such as a digital computer, which has a large amount of stacked modular units.
The Nicholl Patent discloses an apparatus for recharging the rechargeable battery contained in small appliances. The apparatus is designed to have a large quantity of identical small appliances charged successively.
It is desirable to design and construct transformer battery chargers that are used directly for charging independent rechargeable batteries not contained in small electronic appliances. In addition, it is desirable to make transformer battery chargers with various characteristics to suit different types of rechargeable batteries respectively. It is further desirable to increase the efficiency and reduce the cost of manufacturing transformer battery chargers with different characteristics.